Most of the time pests and disease are just nature's way of telling the farmer he's doing something wrong.

Eat all the junk food you want as long as you cook it yourself.

Eat more like the French. Or the Japanese. Or the Italians. Or the Greeks.

The best farming systems are ones where animals and plants are put into a synergistic relationship.

Food is also about pleasure, about community, about family and spirituality, about our relationship to the natural world, and about expressing our identity. As long as humans have been taking meals together, eating has been as much about culture as it has been about biology.

There are certain products that it's worth buying organic just because the alternatives have so much pesticide. There's a list of the dirty dozen that you can get off the Web. Strawberries, potatoes. A handful of crops that have very high pesticide residues if you don't buy organic. If you eat that a lot, that's a good place to invest.

Wrangham cites several studies indicating that in fact humans don't do well on raw food: they can't maintain their body weight, and half of the women on a raw-food regimen stop menstruating. Devotees of raw food rely heavily on juicers and blenders, because otherwise they would have to spend as much time chewing as the chimps do. It is difficult, if not impossible, to extract sufficient energy from unprocessed plant matter to power a body with such a big, hungry brain.